* Package name    : postallow
  Version         : 4.5.1
  Upstream Contact: Edmund Lodewijks <edmund@proteamail.com>
* URL             : https://github.com/edmundlod/postallow/
* License         : MIT
  Programming Lang: sh
  Description     : modern, non-root Postfix (Postscreen) allowlist generator, based on SPF records

 Postallow uses the published SPF records from domains of known webmailers,
 social networks, ecommerce providers, and compliant bulk senders to
 generate a list of outbound mailer IP addresses and CIDR ranges to create
 a allowlist (and optionally a blocklist) for Postfix's Postscreen.
 .
 This allows Postscreen to save time and resources by immediately handing
 off allowlisted connections from these hosts (which we can somewhat safely
 presume are properly configured) to Postfix's smtpd process for further
 action. Blocklisted hosts are rejected before they reach Postfix's smtpd
 process.
 .
 An allowlist for Postscreen (which is merely the first line of Postfix's
 defense) merely allows listed hosts to connect to Postfix without further
 tests to prove they are properly configured and/or legitimate senders.
 A Postscreen blocklist does nothing but reject the connection based on
 the blocklisted host's IP.
 .
 I do use this software, and intend to maintain it. I will need a
 sponsor.
 .
     Edmund Lodewijks